I've heard alot of people saying they swear by the no pest strips.
I'm about to start using them myself.
That and the Bombs will insure that you will not have a big problem.

I'm using both just to be careful.
I seem to have beat them with the bombs.
But you know hoow they are.
So I'm using the pest strips too.
Someone said to put it in the room for 3 days every 60 -90 days.
I'm doing it every 30 days to be sure.